Custom Loss Functions in XGBoost Algorithm for Enhanced Critical Error Mitigation in Drill-Wear Analysis of Melamine-Faced Chipboard

. 2024 Feb 7;24(4):1092. doi: 10.3390/s24041092

Algorithm 4 Extract HOG Features

procedure extractHOGFeatures ( $i m a g e$ )
$g r a d i e n t s \leftarrow$ computeGradients( $i m a g e$ )
$c e l l s \leftarrow$ divideIntoCells( $i m a g e$ )
$h o g F e a t u r e s \leftarrow []$
for each $c e l l$ in $c e l l s$ do
$h i s t o g r a m \leftarrow$ initializeHistogram
for each $p i x e l$ in $c e l l$ do
$g r a d i e n t \leftarrow g r a d i e n t s [p i x e l]$
$b i n \leftarrow$ findOrientationBin( $g r a d i e n t$ )
addToHistogram $(h i s t o g r a m, b i n, g r a d i e n t . m a g n i t u d e)$
end for
$n o r m a l i z e d H i s t o g r a m \leftarrow$ normalizeHistogram( $h i s t o g r a m$ )
appendToFeatureVector $(h o g F e a t u r e s, n o r m a l i z e d H i s t o g r a m)$
end for
return $h o g F e a t u r e s$
end procedure